In many parts of the United States, there has been an unfortunate invasion of fire ants. Fire ants are far more troublesome than ordinary ants, with the bite being much more painful than the bite of ants with which most citizens have become accustomed.
Fortunately, there are several poisons available on the market for controlling these troublesome invaders, with the most successful poison being of the type that is carried down into the burrow, where it reaches the queen. Typical poisons are Amdro, Logic and Spectricide, which are usually purchased in granular form.
Through the years various wheeled devices have been proposed for enabling granular substances and substances in powder form to be dispensed over wide areas of lawns, gardens, fields and the like, and byway of one example, the Schroeder U.S. Pat. No. 2,493,599 entitled "Single-Row Fertilizer Applicator" involves a substantially cylindrical casing or container that may be constructed of sheet metal and that may have a single discharge port or aperture formed in the sidewall of the container near the lower end thereof. Schroeder supports his device from a single wheel, and he provides a valve arrangement as well as a control means therefor. This involves a flexible wire or cable furnished with a finger grip, and by pulling on the finger grip, the user can cause fertilizer to be dispensed in a selected location. Although probably suitable for dealing with fertilizer, this type of device would be needlessly expensive and not highly effective for dispensing a granular substance over a comparatively wide area.
A different approach was taken by Marlek in his U.S. Pat. No. 4,638,948 entitled "Liquid Chemical Applicator for Treatment of a Horizontal Surface," for he utilizes a dual wheeled device having fairly elaborate means for dispensing a liquid chemical by the use of numerous spray nozzles, through which the liquid chemical can be dispensed as a result of the pressure supplied by a pump. This approach would not be suitable for use if the substance being dispensed is in either a granular form or powder form.
It was to overcome the shortcomings and disadvantages of these prior art devices that the present invention was evolved.